Duplex-piston engine.



G. K, GJERDE.

DUPLEX PISTON ENGINE. APPLIOATIOI'I FILED Muis. 1912.

1,49075, @mmm Een. 31, 1912.

la@ 2 25 2! j ,25

of this specification.

GULLIK KRISTOFFERSEN GJERlDE, 0F CHRISTIANI, NORWAY, ASSIGNOB T0 LEVAHN MOTOR CO. A/S., OF CHRISTIANI, NORWAY.

DUPLEX-PISTON ENGINE.

Specification of Letters Patent.

Patented Dec. '31, 1912.

Application filed January 23, 1912. Serial No. 672,959.

10 all vwhom it may concern:

Be 1t known thatv I, GULLIK KRISTOFFER- SEN GJnnnn, a subjectI of the King of Norway, residing at (,lhristiania, Norway, have invented certain new and useful Improvements in Duplex-Piston Engines; and I d0 hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it'appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part My invention hereinafter described, comprises a duplex-piston engine, in which each pistonoperating in its own cylinder, acts as a slide valve connecting the ports of both cylinders.

It includes a special arrangement of steam passages, 'atlording communication between the two cylinders; a special construction of the pistons; and inlet and exhaust steam passages in connection with the other passages aforesaid.

It includes also the special arrangement of these steam passages in the casting which forms or contains the said cylinders.

The said invention is specially, but not exclusively. designed for pumping water or compressing air, and the object thereof, in any condition of use, is to simplify the construction aud to increase the eliiciency of the engine.

lt is illustrated in the accompanying drawings, in which- Figures land 2 represent `a longitudinal section of the engine, showing the. pistons in diii'erent parts of the stro-ke, and in diagrammatic ways, the arrangement of, the steam passages between the cylinders and parts of the cylinders.

In these drawings the body of the engine is marked 1. lt. comprises two cylinders, 2

and 3, formed in the body parallel with each other, and in these reciprocate the pistons A and B, which are of considerable relative length, as indicated in the drawings. These pistons are alike, and each is provided with reduced or turned down portions which, whatever be the position of the piston circumferentially, form steam passages across thecylinder when the reduced portions register with the ports. These reduced portions are marked l-l, 5, 6, and 1l, 12, 13, respectively; and these reducedportions Aare between tour full port-ions or heads which are marked 7, 8, 9 and 10, and 14, 15|, 16, 17, re-` spectively. These cylinders communicate with eachother by passages 30, 31, 32, 33, 3a,

36 and 37, which, as shown, are formed 1n the body or casting between the cylinder,

and which, during the movement of the' pistons, 4may be closed or may be connected with a supply or exhaust pipe respectively according as the ports of the passages register with a head or with a reduced portion of a piston.

I have shown the body as cast in one piece, open at one end and containing cylinders and the passages, this end being closed by a plate, the piston rods passing through. holes in the opposite end.

As the steam enters from the inlet, shown by the arrow, through the passage 18, it passes alternately the ports 19 and 20, through the passages formed by the reduced portions 11 and 13 and also alternately enters cylinder 2 through channels 30 and 33, thus giving impetus to the piston. In the same manner, steam entering cylinder 2 by the passage 2l, is distributed to cylinder 3 by way of the passages 34 and 37, according to the position of the piston. The steam is er-v hausted in a like manner by a system of parallel passages for exhausts, thesepassages, as shown in the drawing being substantially parallel with the inlet passages for the live steam, and they are so arranged, as the drawings sho-w, that the exhaust is automatically closed by the piston when near the end of its stroke, ioning effect.

Assuming the construction and arrange- 'ment of the parts above specied, to be as shown in the drawings and the position .of part-s to be as represented in Fig. 1, the operation of the engine on the admission of steam to the inlet port will be as follows: In' the position shown in F ig. 1 the steam passes through the passages 18 and 21 and through the port 22 to t-he reduced portion 5,l then through the passage 35 into the cylinder 3 on the left hand end of its piston B which accordingly is forced to the right. At Athe same time the steam that has been used, is allowed to escape through the passage 37 ,the reduced portion 6, and the port 26 of the passage 24. By the movement of thepiston B to the right, the passage 30,

thus producing the c'ush-v ais@ be apparent that there, am 1m def and 27 which connu medae cent??? w :mst and suppjy ink@ the, bve steam across am @37h11, the oher, and the same way tak-s ma .haast imm one cylinder the m dw @Klimaat pmt.

The avantages of the @Qnsruc'tin is' spam; of smpijy are obvious, im 'if' ters, @n it does not 'ma'ter n Wha fiom he pistons may have beam iihe ohevwl always be in iaslen ce'v@ liv@ swam @ithercmcy 'verse passage. The psCoI-lfs L a steam for @ach other, engt'h of dm stroke depending onwthe Size of the ew 1 but it is determined beforehand bv t.. stuctlon. The pistonsv are Mikie emi?, mit be comeced to each Gif. actxlg upon them altermgely and t @l @I and in ascmdance with that? respec sons. ncidentally, 'the c mg Cured giver 'each stl-oke am this is matic; im exhaust ;`wv:y"-; dosed 'just bioxe thgend o' the emalder of the cen for eectv@ cus? n, M it will be @bselved that .7, point of grzxest Comprssi will be coping' in im tht.

The ce@ 'uczion and pasmges .e such that the S* gine may b@ m1de,'.m1d s mad@ c casng which smplies zhe and leaves nothing to gsi; 0L @if Quim. have foi 2id ih@ engine b@ 'ry' cal in the use of steam. Thx; @ng @Amd @qixay w Eli for pumm.. 5 mg zur.

mail efs or portions 0j;

portions 3, a duplicate set ot steam passages between said cylinders, one set of live steam passages leading from the central ports of each cylinder to the end ports of the ether, a similar set of passages for the exhaust steam, transverse passages between these duplicate inlet and exhaust passages, all these passages being arranged Ain relation to the full and reduced portions ot the piston, substantially as described.

3. An engine comprising a pair ot parallel cylinders and reciprocating pistons therein, said pistons having full portions or heads t, and intermediate or reduced portions 3, both pistons being circumferentially similar and interchangeable asnd moving freely on their axis, a duplicate set of steam passages between said cylinders, one set of live steam passages leading from the central ports of each cylinderto the end ports ot the other, a similar set ot' passages ior the exhaust. steam, transverse passages between these duplicate inlet and exhaust passages, all these: passages being arranged in relation tothe tull and reduced portions of the piston, substantiallyr as described.

4. An engine comprising a pair of parallel e Ylinder's and reci rocatino istons therein, said pistons having full portions or heads and intermediate or lreduced portions, both pistons being circumferentially similar and interchangeable and moving freely on their axis, and both the pistons moving independent ot' each other but governed .automatilcally by their relative'positions to each other and to the steam and exhaust ports, a duplicate set ot' steam passages between said cylinders, one set of live steam passages leading from the central ports oit' each cylinder to the end ports of the other, a similar -set ot passages for the exhaust steam, transverse passages between these duplicate inlet and exhaust passages, all these passages being arranged in relation to the full and reduced portions of the piston,

substantially as described.

5. A#in cnglne comprising a pair of parallei cylinders and reciprocating pistons therein, said pistons having full portions or heads and intermediate or reduced p0rtions, both pistons beingA cir'cumterentially' duplicate inlet and exhaust passages, allthese passages being arranged in relation to the full and reduced portions off the piston so as to enable the engine to start inV whatever position t-he pistons may' have relative to each other, the one piston being constantly one-halt stroke behind the other, the exhaust passages Vbeing arranged to be put out of operation alternatively by the piston covering them, whereby is formed an eii'ective steam cushion, substantially as described.

G. A duplex engine comprising two parallel cylinders, and pistons, said pistons hav` ing inll and reduced portions, an inlet on one side and exhaust on the other, and steam 4passages' arranged to carry the live steam iirst to one piston and then to the other, and passages QQ, Q3, and 28, Q9, formed in the walls ot the cylinders, substantially as described.

7. In an engine having two full pistons with interior reduced portions, a system of duplicate steam passages leading from both ends of each cylinder, to the interior ports of the other cylinder, and arranged to coact with the reduced portions of each piston, and steam supply and exhaust passages coacting with the steam passages first mentioned, substantially as described.

In testimony that I claim the foregoing (amiesy of this patent may be obtained for ve cents each, lby addressing the Commissioner of Patents, Washington, D. C. 

